Signal device.



D. G. KNITTEL.

SIGNAL DEVICE.

APPLICATION FILED umzs, 1913.

Patented Apr. 14, 1914.

FIG-.4.

;IIl/IliliIl/I!!!Illilllllf WITNESSES:

A TTORN 601.0148 PLANOGKAPH (10., WASHINGTON. n. c.

UNITED STATES PATENT OFFICE.

DAVID G. KNITTEL, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO AMERICAN FIRE ALARM COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF DELA- WARE.

SIGNAL DEVICE.

Specification of Letters Patent.

Patented Apr. 14, 1914.

To all whom it may concern:

Be it known that I, DAVID G. KNrr'rEL, a citizen of the United States, residing at Pittsburgh, in-the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Signal Devices, of which improvement the following is a specification.

My invention relates to electric signal transmitting mechanisms such as are used in police or fire alarm boxes to send desired signals to a central station.

The object of my invention is, generally stated, to increase the efficiency, certainty, and ease of operation of such signal transmitters.

. More specifically stated, it is one object of my invention to provide a contactor for such mechanisms which will, by the operation of the mechanism, be kept free from any deposit of such foreign matter as would interfere with the completing of a circuit.

Another specific object of my invention is to provide a means for locking a portion of the mechanism when not in operation, such locking means being released by the setting of the mechanism in operation and therefore ineffective to retard the movement thereof. And still another specific object of my invention is to provide a switch for cutting out the circuit by closing the box door, the switch being so constructed as to operate freely in the desired manner.

In the accompanying drawing, which forms part of my specification I have illustrated an embodiment of my invention.

Figures 1 2 and 4 are, respectively, front, rear and side elevations of the mechanism; Fig. 3 is a sectional view taken on the line 2-2, Fig. 7, looking in the direction opposite to the arrows attached to this line; Figs. 5 and 6 are sectional elevations on lines 22 and 1-1, respectively, of Fig. 7; and Fig. 7

moved by a box-number wheel 14 and a spec1al-signa-l wheel 11, respectively, the movement of the arms being effective to make and break an electric circuit at contact pens 21 and 22. The mechanism for turning sald Wheels consists of a suitable springactuated clock work train of gears mounted between two plates 1 and 2, which are suitably held in fixed relative positions by means of screws 3 extending through tubes 4. The box-number wheel 14 is mounted upon a shaft H driven directly by the clock work, and the special-signal wheel 11 is secured to a shaft 12, to which there is also secured a toothed sector 16 adapted to be engaged by a corresponding sector 15 borne by the shaft H. The special-signal wheel may be set for any desired signal'by means of an indicator 13 secured also to the shaft 12. The box number and special-signal wheels are provided with peripheral teeth adapted, when the wheels are rotated, to move the arms 25 and 17 which are held yieldingly against said wheels by means of a spring 26, the end of the arm 25 bearing upon the wheel 14, and [the arm 17 bearing upon the wheel 11 through a roller 19. In order to set the transmitter in operation, av handle 5 is secured to a shaft 6, which in turn is connected to the main spring 7.

In the operation of the transmitter as thus far described, the clock Work mechanism, when set in motion by turning the handle 5 through a limited arc, causes the shaft H to make a complete revolution, during which time the peripheral teeth of the boxnumber wheel cause the arm 25 to vibrate according to the number and spacing of such teeth, and thereafter the sector 15 engages the sector 16 thus causing the shaft 12 and special-signal wheel 11 to revolve through an are dependent upon the ore-arrangement or setting thereof, the vibrating of said wheels being efiective to break the circuit through the contact pens 21 and 22.

One feature of my invention concerns the character of the contacting member secured to the arm 17 and extending between the pens 21 and 22. It is desirable that such member be kept free from all foreign matter liable to render a good contact uncertain. To such an end the contactor is a roller 20, rotatably mounted on the end of the arm, and adapted, when the arm is vibrated or oscillated, to revolve a small amount," thereby presenting changing contact surfaces kept clean by the friction of the contact pens thereon.

In signal transmitters, such as are shown herein, it is desirable to provide a shunt circuit so a path of electrical continuity will be afforded other than that through the contact pens, it being understood that, while the in strument is inoperative, a foreign current may flow through the circuit and injure the contact pens. A further desirable feature of such transmitter is a means for locking the special-signal wheel while the instrument is inoperative. In order to simplify the construction and operation of the mechanism I provide a single means for controlling the shunt circuit, for locking the special-signal wheel, and for setting the mechanism in operation. Referring to the embodiment in the drawing of this feature of my invention, the contact pens 21 and 22 are secured to binding posts 23 and 24-, which are electrically connected to the circuit wires as and w. Shunt circuit wires 50 and 51 extend from the binding posts 23 and 24 to posts it and j, to which switch members 10 and 9 are secured, the member 9 being a spring arm adapted to be held yieldingly against the member 10 by means of an arm 8 secured to the shaft 6. A spring arm 5, adapted to engage the special-signal wheel 11 is also secured to the shaft 6, the arrangement being such that the arm 8 closes the switch 9, l0 and the arm I) engages the wheel 11 when the instrument is inoperative (such position being indicated in full lines in Fig. 2), and that by turning the shaft 6 to operate the transmitter the switch member 9 will be released and the arm 6 removed from engagement with the wheel 11 (such position of parts being indicated by dotted lines in Fig. 2). By such an arrangement it will be seen that during the operation of the transmitter the special-signal wheel will be free to move.

It is well known that transmitters of the character described herein are mounted within cast iron boXes having swinging doors which are opened only when it is desired to send a signal. In order to cut the electric circuit from the transmitter various forms of switches have been used such switches being thrown by the closing of the door, and, when the door is opened moved in the opposite direction by the action of a spring. As heretofore constructed, such switches frequently fail to operate when the door is opened, such failure being caused by the binding of the movable parts upon their bearings.

Referring again to the drawing, I provide an annular rotator 28, rotatably mounted on a pinion 52 and provided with suitable contact pieces to switch the circuits as desired. The rotator is provided with an arm 29 the end of which extends into a slot 30 formed in a longitudinally movable bar 27. The outer end of the bar lies in the path of the door of the transmitter-containing boX (not shown herein), the bar being held yieldingly in outward position by means of a spring is. A plurality of spring-arm contactors or pens A, B, C and D, electrically connected at one end to suitable binding posts 34, hear at their other ends on opposite sides of the rotator 28, and thereby prevent the rotator from binding upon pin 52.

The wiring of the switch depends, of course, upon the character of the installation. The rotator shown herein is adapted to cut out a telephone circuit as well as the signal transmitting circuit, although complete connections are not illustrated, the same being well understood by those skilled in the art.

I claim as my invention:

1. In a signal transmitter, the combination of a pair of oppositely disposed contact pens each electrically connected to a circuit, a pivoted arm, means for intermittently moving said arm, and a roller cont actor rotatably mounted on said arm and in one position thereof closing a circuit through said pens.

2. In amultiple signal transmitter, the combination with an electric circuit, boxnumber and special-signal wheels, and moving mechanism therefor; of means including a rotatable shaft for setting said mechanism in motion, and an arm secured to and movable with said shaft and having locking engagement with said special signal wheel wh said moving mechanism is at rest.

3. In a multiple signal transmitter, the combination with a main electric circuit, a shunt circuit provided with a switch, boxnumber and special-signal wheels, and moving mechanisms therefor; of a rotatable shaft for setting said moving mechanism in motion, and means secured to and movable with said shaft for locking said specialsignal wheel and for controlling said switch.

4. In a multiple-signal transmitter, the combination with an electric circuit, boxnumber and special-signal wheels provided with peripheral teeth, and moving mechanism therefor; of means including a rotatable shaft for setting said mechanism in motion, and a spring-arm secured to and movable with said shaft and having locking engagement with the teeth of said specialsignal wheel when said moving mechanism is at rest.

5. In a multiple-signal transmitter, the combination with a main electric circuit, a shunt circuit provided with a spring switch,

box-number and special-signal wheels, and In testimony whereof I have hereunto moving mechanism therefor; of a rotatable signed my name in the presence of two subshaft for setting said moving mechanism in scribing witnesses.

motion, and arms secured to and movable DAVID G. KNITTEL. with said shaft for locking said special- In the presence of-- signal wheels and for controlling said CLARENCE A. WILLIAMS,

switch. JOHN H. RONEY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, I). G. I 

